Transmission of colored pictures



April 19, 1932.

R. SCHMOOK TRANSMISSION OF COLORED PICTURES Filed Sept. 27, 1950 3 Sheets-Sheet l 21 ll frr M INVENTOR RUDOLF 3 HMOOK April 19, 1932. R. SCHMOOK 1,854,315

TRANSMISSION OF COLORED PICTURES Filed Sept. 27, 1950 3 Sheets-Sheet 2 INVENTOR RUDOLF SCH M OOK ATTORNEY April 19, 1932. R. SCHMOOK TRANSMISSION OF COLORED PICTURES 3 Sheets-Sheet 3 Filed Sept. 27', 1930 INVENTOR R U DO LF SC ATTORNEY HMOOK Patented Apr. 19, 1932 RUDOLF SGHMOOK, F BEBLIN-CHABLOTTENBURG, GERMANY, ASSIGNOR TO SIEMENS & HALSKE, AKTIENGESELLSCHAFT, or smivi'nnssrAn'r, nEAnBnnmn, GERMANY,

A CORPORATION OF GERMANY TRANSMISSION OF COLORED PICTURES Application filed September 27,1930, Serial No. 484,809, and in Germany June 13, 1929.

In the telegraphic transmission of colored pictures, whether it was forthepurpose of the production of colored prlnts or the production of autochrom films, according to the prior art, the picture to be transmitted was photographed, as in the known three-color printing process, several times, forinstance, three times making use of filters, and the black and white films thus obtained were transmitted in successive order. At the receiving end these color-selective negatives or positives were used for the preparation of a colored print in the manner that color plates were made therefrom according to the known printing process. g

The principal object and purpose of the present invention consists in the simplification of this complicated process. This is accomplished in such a manner that the finished picture, disregarding the intermediate photographic process, is scanned and transmitted by the scanning device of the picture telegraph transmitter with the use of optic or photoelectric. color selection means.

Due to the absence of the intermediate photographicprocess, not only is the transmission accelerated, which is for instance of advantage in magazines appearing in definite intervals, but there is also insured a much better conformity of the color values.

- With the new process there may be used color-selective black-white negatives or positives for the preparation of color plates for multi-color printing as well as positives in natural color using autochrom receiving materials.

The present invention is illustrated in schematic and diagrammatic form by the accompanying drawings, wherein Figs. 1 to 4.- show some embodiments by way of example for the practical application. of the new process for the preparation of colorselective black-white negatives, or positives, while Figs. rangements for the application of the process to the preparation of natural colored positives.

Referring first to Fig. 1, the picture to be transmitted is stretched on the picture cylinder 1. The scanning device consists of the ponding color v in successive order in the path ofthe rays.

5 and 6 show examples for ar-' rigid manner with one another,

transmitting optical system 2 whose luminous ray strikes through a filter arrangement 3, arranged in the form of a revolving shutter, and through a panchromaticphoto cell 4 to a point of the picture The transmitting line starts from the photo cell and therein is connected a transmitting amplifier SV and at the receiving side a receiving amplifierSE. The receivingend consists of a synchronously running picture cylinder 5 and of the recording device consisting of the receivingoptical system 6, whose liminous ray is controlled'by a Kerr cell'7 connected with the. transmission line.

If it is desired to split the colored picture to be transmitted: into three fundamental colors by means of this arrangement, the arrangement 3 is provided with three corresfilters 12, which are inserted Hence, the transmission takes place three times so that there. are received at the reend three. color selective black-white ceiving which may be made the color pictures from plates required Instead of the exchangeable color filters, corresponding color-selective photo cells may, of course, also be used.

Figs. 2, '3

These three cylinders 16, 17 18, are assumed to be revolving'synchronously and cophasah 1y with one another. Coordinated with each cylinder are the appropriate optical systems and photo-relays. The synchronism is suitably established in any desired manner; for example, the cylinders may either be mounted on one driving shaft, so as to becoupled in or they may be driven by transmission means, as for 'instance by toothed wheels or'cam rods.- Separate drives for each cylinder'may, of course,

to be transmitted.

for the three-color printing.

or not at all, greaterthan withthe and 4' represent arrangements whose use reduces the tr ple time oftrans also be employed, and in such a case, the well known synchronous motors may be used as the primary driving elements.

In Fig. 2 the scanning is accomplished by the play of three luminous rays on the picture stretched on drum 8. The light rays may either be arranged in three parallel lines one below the other or in one line, displaced or off-set side by side.

10, 11, filters being disposed in front of the same for the screening of the undesired color. There may also be employed standard so called Kinox lamps, or a common light source whose light is split by means of an optical arrangement in three individual parts of parallel course. A further possibility consists in the use of three white light rays without color filter and of three coloreselective photo cells. In the case as per example, there are provided three panchromatic photo cells 13, 14;, 15 which are disposed side by side. The vertical arrangement is represented by the cells 13', 14', 14:. Three transmitting channels run from the three photo cells with transmitting amplifier SV and receiving amplifier EV to three receiving drums 16, 17 18, with recording devices 19, 20, 21. The corresponding recording elements at the receiver must assume the same relative position to the picture outline as the scanning elements at the transmitter. The transmitting time resulting from such an arrangement is only slightly larger than in the transmission of a standard black-white picture: namely in the scanningwith three parallel lines one below the other by the time which elapses ,until the light rays sent out bythe second and third photo cell scan the first picture line; in the scanning with photo cells arranged in one line next to one another by the time required by one picture line for turning from the first to the third photo call. In order to characterize the arrangement of the record ing elements in accordance with the scan ning elements 13, 14: and 14, the recording arrangements 13", 14 are shown in dotted lines. The position of the last recording element 21 is for'both systems of arrangements the same, likewise at the transmitter.

The embodiment by way of example shown in Fig. 3 shows the utilizing of a single double-line transmission or of a high frequency carrier wave. To permit the use of this arrangement, the three carrier frequencies modulated with the various picture currents are chosen of different value so that they may be separated at the receiving station by filters F1, F2, F3. In the example of the embodiment, the different carrier frequencies are produced in a manner known as such in the art by three perforated disks 22, 23, 24 inserted in the path of the rays of the scanning elements. 7 The three picture current carrier frequencies, modulated by the As light sources are provided for instance colored glow tubes 9,

photo cell, are amplified by a joint transmitting amplifier SV and a joint receiving amplifier EV. Otherwise the arrangement is the same as in Fig. 2. The production of the various carrier frequencies may also be accomplished in different manner, for instance in that colored glow tubes are fed with alternating potentials of different frequencies.

Fig. 4c shows, maintaining the most essential parts of the arrangement, a modification of the scanning device at the transmitter. The scanning takes place, in contrast to the former systems, in one point and with one luminous ray which is composed of three light rays of different color so that the diffused light returning to the photo cell may impinge on different color-sensitive sectors of the photo cell. The photo cell may, of course,

also be constructed in simple manner panchromatically.

Figs. 5 and 6 show embodiments for the preparation of colored autochrom positives. The essentially diflerentiating feature, as compared to the former examples, consists in the receiving side of the system'where the three color-selective current impulses of a picture element are likewise made to act upon an individual picture element of the receiver. At the transmitter, which again consists of a picture drum 25, a panchromatic photocell 26 and a transmitting optic system 27, there is provided a perforated disk 28 periodically covered with filters of different color. In accordance therewith, the receiver is equipped with a'perforated disk 29 of similar composition than the former. The color filters in the perforated disks are arranged in periodic succession (blue, red, yellow, blue, red,=yellow, etc). The speed of the picture drum relative to the one of the perforated disks is cal-" culated in such that each picture element is scanned one after the other by three different colors. On the receiving side with the recording of this picture element the three same colors are accordingly brought in the path of the rays of the recording lamp so that the autochrom film reproduces the picture element in the natural colors. I

Fig. 6 shows an arrangement conforming with the transmitting end to Fig. 4 in its essentials, the three picture currents again being recorded in one point of thereceiving cylinder. This arrangement is insofar more advantageous than the installation according to Fig. 5 in that the scanning and the recording are not accomplished one after the other, even if in a short time. but absolutely simultaneously with the result that very sharp pictures, and very true to nature, are obtained.

Other modifications and changes may suggest themselves to those skilled in the art to which the invention relates, and I, therefore, believe myself to be entitled to make and use any and all of such modifications as fairly fall within the spirit and scope of the hereinafter appended claims.

Having now described my invention, What I claim and desire to secure by Letters Patent is the following:

1. A system for transmitting and reproducing colored picture records which comprises a record carrying drum, a plurality of illumination sources of different colored light, means for directing the light from each of said sources to a common point on the record carrying drum for illuminating the same, means for cyclically interrupting the light from each of the sources directed toward said record quency, and a panchromatic light translating element adapted to be influenced by the variation in each color of the record surface as determined by the illumination thereof for producing amplitude modulated output signals of a plurality of difierent amplitudes and frequencies corresponding in number to the number of colors selected for transmiss1on.

2. A system for converting colored picture records into electrical impulses corresponding to the coloration of different selected component colors which comprises a panchromatic light translating element sensitive to each of a plurality of selected component color, means for illuminating the colored picture record by a plurality of lights each of different colors for illuminating the light translating element in accordance with the different selected component colors, and light chopping means for controlling the illumination of the light translating element by each of said component colors at different interruption frequencies for producing amplitude modulated output currents from the light translating element of a plurality of diflerent frequencies corresponding in numher to the number of component colors select-ed for transmission.

3. In a system for transmitting electrical impulses corresponding to colored picture records, the method which comprises illuminating a colored picture record by a plurality of different colored light sources, interrupting the light for illuminating the record from each of the light sources cyclically at difierent rates, converting the varying intensities of the different colored markings on the'record as determined by the illumination into proportionate strength electric current impulses of a frequency corresponding to the rate of interruption of each of the illuminating lights and each of an amplitude corresponding to the intensity of color of each of the colors of the picture record.

i. A system for converging varying intensities of predetermined primary colors on a colored picture record into proportionate strength electric current impulses which comprises means for illuminating the record by drum at a different fre a plurality of different lights corresponding to each of the selected primary colors, means for cyclically interrupting the light issuing from each of the sources at predetermined and diiferent rates, and means for converting the intensity of coloration of each of the primary colors of the picture record into a series of wave trains of electrical energy of different frequencies and different amplitudes, depending upon the rate of interruption of the illuminating source and the intensity of coloration on the picture record.

In testimony whereof I affix my signature.

RUDOLF SCHMOOK. 

